Hi,
Enclosed please find a pair of patches that perform some additional cleanup
that was suggested by Boris, Jan and Thomas.
Specifically: this resync's arch/x86/include/asm/xen/cpuid.h from its
upstream source in the Xen tree, and then uses one of the new #define-s to
replace a constant in x86/xen/time.c that was previously only numerically
defined. Pedantic code from v1 is dropped in favor of a more appropriate
return statement.
Changes from v1:
- Coding style fixup in arch/x86/xen/time.c (Feedback from Thomas Gleixner)
Krister Johansen (2):
xen: update arch/x86/include/asm/xen/cpuid.h
x86/xen/time: cleanup xen_tsc_safe_clocksource
arch/x86/include/asm/xen/cpuid.h | 22 ++++++++++++++++++----
arch/x86/xen/time.c | 7 ++-----
2 files changed, 20 insertions(+), 9 deletions(-)
--
2.25.1
Update arch/x86/include/asm/xen/cpuid.h from the Xen tree to get newest
definitions. This picks up some TSC mode definitions and comment
formatting changes.
Signed-off-by: Krister Johansen <[email protected]>
---
arch/x86/include/asm/xen/cpuid.h | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/xen/cpuid.h b/arch/x86/include/asm/xen/cpuid.h
index 6daa9b0c8d11..a3c29b1496c8 100644
--- a/arch/x86/include/asm/xen/cpuid.h
+++ b/arch/x86/include/asm/xen/cpuid.h
@@ -89,11 +89,21 @@
* Sub-leaf 2: EAX: host tsc frequency in kHz
*/
+#define XEN_CPUID_TSC_EMULATED (1u << 0)
+#define XEN_CPUID_HOST_TSC_RELIABLE (1u << 1)
+#define XEN_CPUID_RDTSCP_INSTR_AVAIL (1u << 2)
+
+#define XEN_CPUID_TSC_MODE_DEFAULT (0)
+#define XEN_CPUID_TSC_MODE_ALWAYS_EMULATE (1u)
+#define XEN_CPUID_TSC_MODE_NEVER_EMULATE (2u)
+#define XEN_CPUID_TSC_MODE_PVRDTSCP (3u)
+
/*
* Leaf 5 (0x40000x04)
* HVM-specific features
* Sub-leaf 0: EAX: Features
* Sub-leaf 0: EBX: vcpu id (iff EAX has XEN_HVM_CPUID_VCPU_ID_PRESENT flag)
+ * Sub-leaf 0: ECX: domain id (iff EAX has XEN_HVM_CPUID_DOMID_PRESENT flag)
*/
#define XEN_HVM_CPUID_APIC_ACCESS_VIRT (1u << 0) /* Virtualized APIC registers */
#define XEN_HVM_CPUID_X2APIC_VIRT (1u << 1) /* Virtualized x2APIC accesses */
@@ -102,12 +112,16 @@
#define XEN_HVM_CPUID_VCPU_ID_PRESENT (1u << 3) /* vcpu id is present in EBX */
#define XEN_HVM_CPUID_DOMID_PRESENT (1u << 4) /* domid is present in ECX */
/*
- * Bits 55:49 from the IO-APIC RTE and bits 11:5 from the MSI address can be
- * used to store high bits for the Destination ID. This expands the Destination
- * ID field from 8 to 15 bits, allowing to target APIC IDs up 32768.
+ * With interrupt format set to 0 (non-remappable) bits 55:49 from the
+ * IO-APIC RTE and bits 11:5 from the MSI address can be used to store
+ * high bits for the Destination ID. This expands the Destination ID
+ * field from 8 to 15 bits, allowing to target APIC IDs up 32768.
*/
#define XEN_HVM_CPUID_EXT_DEST_ID (1u << 5)
-/* Per-vCPU event channel upcalls */
+/*
+ * Per-vCPU event channel upcalls work correctly with physical IRQs
+ * bound to event channels.
+ */
#define XEN_HVM_CPUID_UPCALL_VECTOR (1u << 6)
/*
--
2.25.1
Modifies xen_tsc_safe_clocksource() to use newly defined constants from
arch/x86/include/asm/xen/cpuid.h. This replaces a numeric value with
XEN_CPUID_TSC_MODE_NEVER_EMULATE, and deletes a comment that is now self
explanatory.
There should be no change in the function's behavior.
Signed-off-by: Krister Johansen <[email protected]>
---
arch/x86/xen/time.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 95140609c8a8..94056013a2a4 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -20,6 +20,7 @@
#include <asm/pvclock.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
+#include <asm/xen/cpuid.h>
#include <xen/events.h>
#include <xen/features.h>
@@ -495,11 +496,7 @@ static int __init xen_tsc_safe_clocksource(void)
/* Leaf 4, sub-leaf 0 (0x40000x03) */
cpuid_count(xen_cpuid_base() + 3, 0, &eax, &ebx, &ecx, &edx);
- /* tsc_mode = no_emulate (2) */
- if (ebx != 2)
- return 0;
-
- return 1;
+ return ebx == XEN_CPUID_TSC_MODE_NEVER_EMULATE;
}
static void __init xen_time_init(void)
--
2.25.1
On 22.02.23 18:54, Krister Johansen wrote:
> Hi,
> Enclosed please find a pair of patches that perform some additional cleanup
> that was suggested by Boris, Jan and Thomas.
>
> Specifically: this resync's arch/x86/include/asm/xen/cpuid.h from its
> upstream source in the Xen tree, and then uses one of the new #define-s to
> replace a constant in x86/xen/time.c that was previously only numerically
> defined. Pedantic code from v1 is dropped in favor of a more appropriate
> return statement.
>
> Changes from v1:
>
> - Coding style fixup in arch/x86/xen/time.c (Feedback from Thomas Gleixner)
>
>
> Krister Johansen (2):
> xen: update arch/x86/include/asm/xen/cpuid.h
> x86/xen/time: cleanup xen_tsc_safe_clocksource
>
> arch/x86/include/asm/xen/cpuid.h | 22 ++++++++++++++++++----
> arch/x86/xen/time.c | 7 ++-----
> 2 files changed, 20 insertions(+), 9 deletions(-)
>
For both patches:
Reviewed-by: Juergen Gross <[email protected]>
Juergen